Carburetor



Bf B. BRIGGS CARBURETOR De'c. 1, 1931.

Filed July 20,. 1926 2 Sheets-Sheet l B. B. BRIGGS Dec.v1, 1931.-

CARBURETOR Filed July 2O,y 1926 2 Sheets-shew'l 2 y Z i5 www .Patented Dec. 1, ,1931

` UNITED STATES Limi APATENT OFFICE Application med my ao,

This invention relates to carburetors for 4 internal combustion engines and forms a continuation in part of my prior application filed March 13, 1,926, Serial Number 94,549.

More particularly the invention relates to the fuel bowl or reservoirof such acarburetor.

One important object. of the invention is to provide an'improved arrangement whereby the fuel in the lower part ofthe carburetor is well heated previous to its`- entering the nozzle in the mixing chamber of such carburetor thus permitting the use of :a low grade of liquid fuel. A second important object of the invention is to provide an improved form of such a carburetor whereinthe liquid hydrocarbon fuel is maintaied at an even temperature while running. p

A third important object ofthe' invention is to provide improved adjustable means for governingthe temperature of the fuel, the

carburetor being also providedwith indicating means for the' temperature whereby the correct, adjustment of the temperature governing means may be obtained.

A fourth important object of the invention is to provide an improved and novel form of bowl and arrangementbf air intake therein.

A fifth important object of the invention is to provide an improved arrangement of fuel controlling float 1n such a carburetor.

' will be hereinafter apparent, the invention 'A sixth important object of the invention is to provide impro/ved means for holding the fuel bowl and the air inlet and mixing cham- 'ber assembled.-

With the above and other objects in view as consists in general of certain novel details of construction and combinations of. parts hereinafter fully described, illustrated in the accompanying Y drawings and specifically claimed. y g

In the accompanying drawings like characters of reference indicate like parts in the several views, and:

Figure 1 is a side elevation of the improved carburetor applied to an engine, the view being partly in section to show certain features.

' Jthe llne 3-3 of Figur Figure 4 is a section onthe line 4 4 of L y bowl or fuel reservoir havin and side wall 11. This bowl 1s of elongated 1998. Serial No. 123,741.

Figure 2 is an enlar end elevation of the carburetor removed m the en le. k

Figure 3 is an enlarged detai Fi re 2.

igure 5 is a section on Fi rc2.

igure 6 is a detail view, partly in section, showing thearrangemeitt of the two piece top or cover for the bowl.

The carburetor as constructed in accordance with this` invention is provided with a a bottom 10 the line 5-5 of form having parallel side walls and semicircular end walls. Beneath the bottom 10 in spaced relation thereto is a hot gas jacket bottom 12 which extends at its periphery be yond the bottom of the bowl and carries an upstanding side wall 13 connected to the side Wall of the bowl at its top by a top wall 14. i

Thus beneath the bottom and around the lower part of the bowl extends a hot gas jacket which is highY enough to at least reach the normal fuel level in the bowl. Between the bottoms 10 and 12 there is formed a 1on- `gitudinally extending baiile rib 15 which runs from one end wall of the bowl towards the other and terminates short of the end portion of the wall 13. Thisbaiilerib has a laterally enlarged portion 16 positioned centrally of the bowl so that a suitable opening may be formed therein for the reception of a tube having a vertical portion 17 provided with a threaded lower end, and a horizontal portion 18 having a securing` flange 19 at its extremity by means of which it may be secured to the engine VE in the usual manner. Just above the threaded end the tube is provided with an annular flange 20 which seats in a'suitable rabbet formed in the bowl bottom and on this threaded end is screwed a sleeve nut 21 which thus secures the tube and bowl firmly together. dially inward from the side of the tube 17 at a point just above the bottom of the bowl is a small tube 22 which has its terminal portion 23T-,turned upwardly in the `ixis of the tube 17. The opening in the upper end of setcion on j Extending raf wherein is screwed the threaded portion of a and thereby prevent further entry offuel lthis tube 23 is controlled by a needle valve the wall 43. The thermometer casin is pro- 24 having a threaded portion 25 on its stem vided with a cap carrying a bracket 4 wherewhich is screwed through a suitable threadto a lever 48 is pivoted intermediate its ends. ed opening in the bend between the portions One arm of this lever is pivoted-to a bracket 17 and 18 of the air tube. A knurled head 49 carried by the cell 37 while the other arm Ienables this valve to be 'adjusted as desired. has the threaded upper end of a link 50 pass- A vent 26 leads from the upper part of the ing in a` substantially vertical direction bowl to the upper part of tube 17 As thus therethrough. The lower end of this link is constructed the lower part of tube 17 constipivoted to the end of a valve lever 51 fixed to tutes an air intake while the upper part the stem of a butteriiyvalve 52 located in the forms a mixing chamber. e A nipple 38. A spring 53 urges this arm 51 to Thecover for the bowl consists of two simraised position and a nut 54 threaded on the ilar halves 27 meeting in a straight line link 50 below the lever 48 limits the lift of which passes through the axis of the tube 17. this arm' with respect to the lever and conse- Each of these halves has a rounded end quently controls theopening of the valve`52. which is secured to the wall 11 by a screw 28 As the heat of the fuel in the bowl rises the and other screws 29 pass through notches in cell 37 expands and the valve 52 is moved to-` the coacting edges of the cover so that the ward closed position and thus the hot ases heads of these screws 29 bear equally on both are restricted in their flow around the owl. halves of the top or cover and hold' them 1n Conversely if the fuel cools, the valve will be place. On one of these heads is an elxteropened wider. Thus the fuel is kept at a nally threaded nipple 30 for connection to a nearly uniform temperature while the engine fuel/ supply pipe 31 receiving-fuel from a is running. The degree of this tem erature suitable source of supply (not shown). The may be controlled by adjustment o the nut lower end of the nipple 30 has its openingM 54. controlled by a needle valve 32 the stem of A drain cock 55 is provided for the bowl which is slidabl7 supported by yokes 33 seand a throttle valve 56 is provided to control cured to the bow 18 fixed a ioat 34 so positioned that aS Soon aS 'lhere has thus been provided a simple and the fuel rises in the bowl to the proper level eiiicient device of the kind described and for the ioat will act to seat the needle valvey 32 the purpose specified.`

It is obvious that minor changes may be until a portion of .that in the bowl has been made in the form and construction of the indrawn off. vention without departing from the material It will be noted that this arrangement prospirit thereof. It is not, therefore, desired vides for a direct lift of the need e valve and to confine the invention to the exact form dispenses with the use of toggles or levers.

The other half of the top is a depending internally threa herein shown and described, but it is desired provided w1tl1 to include all such as properly come within ed nipple 35 the scope claimed.

Having thus described the invention, what thermostat having a bulb 36 extending downis claimed as new, is: wardl below the fuel levelof the bowl and 1. In a carburetor, a bowl having a top and provi ed on its upper and outer end with an a bottom, a nipple adapted for connection to expansion element 37 here shown as a single a source of fuel supply carried by the bowl expansion cell thou h itgis obvious that there top,vertically alined yokes supported within may be as many of t ese bells as are necessary the bowl at the top and bottom thereof, an to effect proper working of the device. open full gap between the top' of the lower On one side of the carburetor is a nipple 38 yoke and ,the bottom of said bowl, a needle for the admission of hot gases -while a simivalve supported in said yokes for vertical slid-4 lar nip le 39 on the other side provides an exing movement and positioned to close the haust or such gases. Hot gas is preferably nip le opening when raised, and a iioat carsupplied to the nipple through a tube 40 rie by said valve. v

which penetratesthe wall of the en ine eX- 2. In a carburetor, a liquid fuel bowl, a

haust pipe 41 and has its end bevele to face chamber for hot gases around said bowl, gasl the flow of the gases of combustion passing supply and exhaust nipples communicating from the engine. Similarly the exhaust from with said chamber, a valve for controlling the nip le 39 is carried by a tube 42 back the flow of gas into the chamber, athe'rmostat tothe pipe 41, this tube 42 having a beveled having Aa bulb within the bowl and an exe'nd facing away from the gas ow throughl pansioii cell at its upper end, a bracket sup' said exhaust pipe. Screwed into ahorizontal `ported from said bowl, a lever pivoted bewall 'of the bowl is a thermometer casing 44 tween its ends on said bracket and havin one containing a thermometer 45 the mercury of end carried bysaid cell, a valve lever xed which may be observed through a window 46 to the valve, a link fixed to the end of the in the part of the casing which extends above valve lever and extending through the rebottom 10 and to the underthe iow of carburized air through the tube side of the top half 27. On this stem is or pipe maining end of the first mentioned lever, an adjusting nut threaded on said link and bearing against the under side of said {irst lever,

and a spring connected to said valve lever and urging the valve to open position.

In va. carburetor, a bowl, a chamber for hot gases around said bowl, gas supply and exhaust nipples communicating with said chamber, a valve for controlling the flow of gas through the supply nipple, a thermostat having a bulb within the bowl and an expansion cell at its upper end, a bracket supported from said bowl, a lever pivoted between its ends on said bracket and having one end carried by said cell, a valve lever fixed to the valve, a. link connecting said levers and means to adjust the effective length of said link.

4. In a carburetor having a liquid fuel reservoir, a chamber on the under side of said reservoir, an inlet port and an outlet port communicating with said chamber at one side thereof, a rib in the chamber having one end in engagement with the side of said chamber between said ports and the opposite end spaced from the opposite side of said chamber for directing heat therein from the inlet to outlet port, said rib extending from a point on the wall of said chamber between said in` let and outlet to a point adjacent to the 0pposite Wall of said chamber, and means connected with the inlet port to supply heat to said chamber, for the purpose set forth.

5. In a carburetor, a liquid fuel bowl, means for heating the fuel in said bowl, a thermostatic device controlled by the temperature of the fuel in said bowl, means actuated by said thermostatic device for controlling said heating means, an adjustable connection between said device and said second rentioned means and temperature vindicator visible -externally of said carburetor howing the temperature of the fuel in said owl.

6. In a carburetor, a liquid fuel bowl, a

heating chamber about said bowl, a tube for conveying a hea-ted fluid to said chamber, a

thermostatic device controlled by the temperature of the fuel in said bowl, a shut-oli:` in said tube, a connection whereby said device actuate's said shut-off, adjusting means in said connection for determining the degree of actuation of said shut-off and a temperature indicator visible externally of the carburetor showing the temperature of the fuel in said bowl.

In testimony whereof I afiix my signature.

BURDETT B. BRIGGS. 

